351w roller vs 351 non-roller blocks

[Pman1961]

I have an opportunity to purchase a new 408w stroker short block. It has a 4340 crank, h beam rods, SRP pistons with a main girdle. Block work and assembly was done by a reputable shop. It appears that this is a 1969 year block. He told me the engine code was C4AE-8016-A 2 and was hard to read so I would assume it is a C9AE etc. C, I understand is the decade of the motor which is 60's and 9 being the year. I assume that it is a 9 because the 351 windsor was not manufacturered until 1969 am I correct? The following are a list of questions I hope you good guys can answer: I'm sure this is a 2 pc rear main seal. Will this block be prone to rear main seal leaks? Are roller block items such as water pumps, flywheel, etc. interchangeable with non-roller blocks other than the lifters? Will there be any additional work to make the non-roller a roller block other than the use of retro-fit lifters or drill and tap for spyder? The rotating assembly is balanced for the 28 oz dampner and flywheel. If the motor is making 550hp or less is there any advantages of the internal balanced assembly? Also, will the main girdle work with the front sump oil pans? Any other advantages or disadvantages would be appreciated.